The reason that this damaging plant causes so much alarm is that it can begin growing again from just a fragment of its root structure or rhizome. These roots are able to grow down as deep as nine feet which means getting rid of any infestation is never just a simple matter of digging it up.
Tailored Japanese Knotweed treatments for infestations across North West England
We use tried and tested methods of Japanese Knotweed removal. After assessing the problem, we’ll be able to recommend the removal solution that is best suited to your property. We’re open and transparent about our billing, which means you won’t experience any hidden costs or surprises further down the line.
Biological control or cutting
Japanese Knotweed has few if any natural enemies in this country and biological control could eventually become your preferred option. This method would control the plant but not eradicate it.
Regular cutting or pulling will eventually exhaust the plant into submission. However, the time scale, labour, and the cost make this method impractical in most cases.
The stem injection method
This Japanese Knotweed treatment method involves the team at Helmrig Ltd delivering a high dose of glyphosate-based herbicide directly into the Japanese Knotweed stem. This method is not weather dependent and directly targets the specific plant species without harming your surrounding plants. It is labour intensive as every single stem will need to be injected and is only suited to smaller infestations.
Herbicide spray treatments
The most common method we use is the application of herbicides which is effective treatment on larger areas of infestation as well as individual plants. This method offers the use of a broader range of potential herbicides though care should be taken, and you should seek the advice of one of our in house BASIS Qualified Advisor. This method of treatment should only be undertaken out by our NPTC qualified team.
The timescales for complete herbicidal eradication vary depending on the site variables. After surveying each site will be allocated a bespoke herbicidal eradication programme considering all aspects such as the client’s time scales, ecological issues, neighbouring issues and the current health of the infestation.
Excavation & Offsite Disposal
Where there is insufficient space or time to allow for on site treatment options it is possible to excavate and remove Japanese Knotweed material to licensed landfill facility. This is often referred to as ‘dig and dump’.
Many contractors will blindly quote the Environment Agency 7m X 3m guideline which will result in a huge volume of material being removed at great expense to the client whereas a considered approach and supervised excavation by experience personnel will chase the Knotweed plant out and can significantly reduce this volume sometimes by up to 90%.
Japanese Knotweed is a controlled waste and care should be taken that appointed contractors carry the appropriate waste carriers license and that waste transfer notification is provided showing the appropriate EWC code, site of origin, waste carrier, disposal facility and that the document is signed by the appropriate persons.
Helmrig can provide all required machinery and personnel for each project and our in-house trained operatives provide resources to reduce the amount of material going to landfill by up to 60% therefore greatly reducing costs to the client. Helmrig operatives also control the works directing excavations and loading to ensure all legislations are adhered to and that no cross site contamination occurs.
Helmrig have strong relationships with several registered landfills across all regions of the UK and Ireland which we call upon to ensure the most competitive rates are achieved for our clients.
Excavation & Onsite storage
Where treatment cannot be carried out in situ due to the location of the infestation or the timescale of the development infestations are excavated and removed to an on site storage location for further treatment, usually by means of herbicide spraying. Once treated material can be utilised back into the site.
This treatment option adds additional cost to the standard herbicide spray treatment, however it often means development can continue unhindered providing there is sufficient room to store material within the site.
Where sufficient storage areas are not available on site for on-going herbicide treatment it may be possible to create a burial cell. The cell is lined with a specialist geomembrane, such as Cutex into which the excavated Japanese Knotweed is placed and encapsulated.
This option requires excavation of a suitable cell area ideally away from areas of any future ground works or the locations of any services. Liaison with the local Environment Agency officer will also be required to ensure the material is suitable to be buried and the area plotted onto a site plan for future reference.
Japanese Knotweed and contaminated soil can also be buried on site inside a heat sealed plastic membrane. This is ideal where no construction work has begun and the site can be fully excavated to make a hole deep enough to contain the Japanese Knotweed.
The burial site must not be disturbed after excavation and the re-burial location should be clearly marked on all site plans. The Environment Agency will need to be advised that the burial of Japanese Knotweed is taking place and all plans must be approved by them. It is very important that every trace of Japanese Knotweed is removed as a piece the size of a finger nail has the potential to regrow.